What Sonar Do I Need for BioBase Mapping? – Updated

What kind of sonar hardware should I buy for BioBase Mapping is the most common question we are asked. Admittedly, continual change in technology, products, and features can be intimidating and sometimes confusing. With this blog, we focus on what you need to know to get started with BioBase. We start with the Portable BioBase Kit – an off-the-shelf portable solution that has everything you need

What Sonar is compatible with BioBase?

BioBase has an ownership history with the Navico Group (a Division of the Brunswick Corporation). The Navico Group owns the major marine brands Lowrance, Simrad and C-MAP. BioBase LLC is now independent from the Navico Group but remains a partner. For now, BioBase processes the raw sonar format (.slg, .sl2, and .sl3) from ONLY these brands.

The BioBase Portable Kit – an off-the-shelf portable solution that has everything you need

We recently designed a portable kit that would have most everything a new user would need to get started mapping lakes with BioBase including a 9″ Lowrance Elite FS display, a “3in1” transducer that includes traditional and side-scan, a portable case and transducer bracket, external GPS antenna, necessary networking cables and microSD card for recording sonar data. If you need something that will get you started quick and portable, read no further. These can be purchased direct from BioBase with bundle discounts available for first time BioBase subscribers. See the instructions on the BioBase website on how to order. We also have this slick video walking you through how to assemble your kit out of the box

Lowrance or Simrad?

Lowrance is the most popular brand (Elite and HDS product lines) used for BioBase because BioBase has historically been used in inland waters and Lowrance is the major brand in this market. Its design to be mounted externally on smaller inland vessels also has some advantages over its sister brand Simrad. Alternatively, for coastal users looking for a sleek in dash mount and other sonar or charting features more common for sea-going vessels, Simrad (Evo NSS product line) might be preferred over Lowrance. Most transducers, sensors and accessories are compatible and interchangeable between both brands.

The number behind the model name is the screen size in inches

Within each product line, the difference in price is largely due to the screen size. Seven inch screens are the most affordable, compact and consume the least amount of power for portable applications. But you will find yourself squinting to see detail if you have your screen split multiple ways to see a chart, sonar, and other important digital readouts (e.g., depth, water temp, speed, etc). The real-estate on a 12 or 16 inch screen is great for seeing detail, but they come with a modestly higher cost as well. A 9-inch screen represents the Goldilocks for most applications.

Lowrance HDS product line is best, Elite product line is good

Lowrance HDS (or Evo in Simrad) is the premium product line and typically has the best screen resolution/clarity, processors, and other features for users who put lots of hours on the water and demand the most rugged, highest quality product. Much like evolution in the mobile phone industry, HDS product lines have changed names through the years, each bringing new features/upgrades (Gen2-Gen3-Carbon-Live-Pro).

The Elite product line (now called Elite FS) is the best seller and has most features in common with HDS. Elite FS a solid performer and meets most budgets. The primary downside of Elite FS is only one MicroSD card slot. Not a big deal for users in the US where the C-MAP Discover On-board is a highly detailed base chart, but in the rest of the world, the base map on Elite FS is very low detail. In this situation you can’t upgrade the base chart with a C-MAP chart card, because you need that card slot for recording and saving the sonar files for BioBase maps. Still, a highly detailed base chart is not required for creating BioBase maps. Hook Reveal or now Eagle is the entry level unit and will work ok, but avoid bundling with the split-shot or triple-shot transducers as they have a very wide beam 44 degrees (twice as wide as the HDI transducer). Beam angles wider than 22 degrees will result in imprecisions in bottom mapping over steep slopes or deep depths. You can calculate the exact beam angle by recalling a mnemonic from high school trigonometry that you thought you’d never use in real life: SOH CAH TOA. In this case, we are interested in TOA. Tangent = Opposite/Adjacent. Divide your beam angle in half and take the Tangent. Multiply that quantity by your depth. That will give you the cone radius. Multiply that value by two and you have your beam width at a specific depth. So the beam spread of a 44 degree beam angle transducer at 10 ft = approx. 8 ft. A 22 degree beam angle would give you a 4 ft cone footprint in 10 ft of water. Maybe not a big deal in shallow ponds. It’s a bigger deal when you are mapping deep, highly variable bottoms.

A broad range of transducers are compatible with BioBase. 200 kHz is mandatory, but down- and side-scan are “nice to haves”

Transducer installation is about the most important part of the entire process of creating a good map. Please read this post before you install your transducer. For most applications, 3 in 1 transducers (traditional 83/200 khz, 455/800 down- and side-scan) come bundled with Lowrance displays and are recommended. At the minimum, you will need a transducer capable of logging 200 kHz. For deep water mapping (consistently greater than 100 ft or 30 m), consider a higher powered Airmar transducer. The Airmar SS260 with a 6-deg cone is recommended for thru-hull installations and the equivalent TM260 for transom mounts.

For the best side-scan imagery possible, run HDS Pro with Active Imaging HD

For console-steer boats, get an external GPS antenna and NMEA network kit.

Aligning your GPS with your transducer is one of the most important, yet overlooked installation requirements for creating quality BioBase maps. For a tiller-steered boat, the GPS in the display is already lined up with a transom mounted transducer, so an external antenna might not be necessary. However, if the display will be mounted more than a couple of feet or a meter away from the transducer, get an external GPS antenna (Lowrance Point-1, Simrad GS25 or Simrad HS75). Further, external GPS antenna have heading compasses that give users better positional awareness, will help with navigating, and will generate better side-scan imagery. For 95% of lake and pond applications, the accuracy and precision of the Point-1 is more than sufficient. For application that require differential correction, you can network any third party NMEA-compatible DGNSS device. Also, if you purchase an external GPS antenna, you will need to install a NMEA 2000 network on your boat. The minimum you need to get started is a NMEA 2000 starter kit.

Where can I buy?

BioBase LLC is an approved reseller of Navico-branded equipment and ships direct to customers in the US and Canada. Contact us at sales@biobasemaps.com with your hardware needs and we’ll give you install advice, pricing and availability for the product(s) you need. For those outside of the US, you can use the dealer locator here https://dealers.lowrance.com/ to find a reseller near you or contact us direct to help in your search

Ok, how do I power this thing? Battery options

Cranking Battery

Unlike most other consumer devices, these things do not come with their own power. You’ll need to brush up on your wire splicing skills and connect your Lowrance (and Point-1 GPS) to 12 Volt DC power (10.8-17 Volts). Most users have an onboard “cranking” battery to power up the motor and other accessories, tying into this power for your sonar works just fine. Use 12-14 ga marine tinned wire with a 3A inline fuse (included). Depending on your NMEA connector and set up, you may need to power the NMEA network (and Point-1 GPS) separately from the Lowrance display. It’s wise to wire these to a switch if you have a permanent install. If you do not wire the NMEA network to a switch, it will continue to use power and drain your battery.  Add a voltage overlay on to your Lowrance screen so you know how many volts is running from the battery to your display. Old-school Lead-acid batteries are good, Absorbed Glass Mat (AGM) better, and Lithium Iron Phosphate (LiFePO4) battery is the best if you need serious power.

Lithium LiFePO4

For portable applications, Lithium battery technology is great. A LiFePO4 is about a quarter of the weight compared to Lead-acid and AGM and last twice as long. So you pay a little more for them. If you are trying to power a 9″ Lowrance Elite FS or HDS, do not go smaller than a 15 amp hr LiFePO4 battery. A 30Ah battery is a good size, won’t break the bank, and will give you a couple of days of life before a recharge is needed. Pay close attention to match up the right charger for the right kind of battery and use a battery tender that manages and maintains the proper voltage that maximizes battery life.

What’s next?

After you acquire your hardware and get it installed (for the novice, we recommend a certified Lowrance or Simrad Installer), then you are ready to map! Please visit our support resources page and getting started blog before you embark. The power of BioBase is that we automate all the hard work of generating aquatic habitat maps once you get your hardware installed. If you haven’t yet, register for free at biobasemaps.com and we’ll get you started with a free trial.